#!/usr/bin/env python
# -*- coding: utf-8 -*-
# @Time    : 2017/9/26 14:24
# @Author  : shwy
# @Site    : http://ishwy.me
# @File    : for.py
# @Software: PyCharm

'''
for循环:
    sum = 0
for x in [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]:
    sum = sum + x
print sum


raw_input:
    始终会返回string,所以要跟int比价的话,需要使用int()转换成int类型
    
'''

birth = int(raw_input('birth: '))

if birth < 2000:
    print '00前'
else:
    print '00后'
